Rutstroemia tiliacea
Rutstroemia tiliacea (Fr.) K. & L. Holm, Symbolae Botanicae Upsalienses 21(3): 7 (Holm and Holm 1977)
≡ Peziza tiliacea Fr., Systema Mycologicum (Lundae) 2(1): 76 (1822).
≡ Encoelia tiliacea (Fr.) P. Karst., Bidrag till Kännedomav. Finlands Natur och Folk 19: 218 (Karsten 1871).
≡ Cenangium tiliaceum (Fr.) P. Karst., Rev. Monag. Ascom.: 145 (1885)
≡ Phibalis tiliacea (Fr.) Korf & L.M. Kohn, Memoirs of the New York Botanical Garden 28: 116 (Korf and Kohn 1976).
Apothecia with a short stout stipe, erumpent from small black round holes in host’s periderm, singly or in small fascicles, cupulate, leathery, outside radially fibrillose, ochraceousbrown. Disc 4–8(−10) mm in diam., ochraceous- to dark chestnut-brown, margin slightly protruding and crenulate. Stipe basally black, forming black demarcation lines inside the wood. Ectal excipulumof t. prismatica-porrecta, oriented horizontally, main layer of hyaline to brownish cells *7–14 μm wide, external hyphae roughened by pale yellowish to red-brown exudate, 4.5–6.5 μm in diam., loosely attached, causing the fibrous exterior. Medullary excipulum of t. intricata, hyaline or with light brown hue, hyphae *3–10 μm wide, slightly rough. Asci cylindric-clavate, *117–165 × (9–)10–11.5 μm {4}, †95–130 × 8–10(−11) μm {2}, spores obliquely biseriate in living asci, pars sporifera *31–38 μm; apex truncate-rounded, IKI and MLZ faintly to strongly blue (somewhat T-shaped), Sclerotinia-type (reduced, without protruding lower ring); arising from croziers (partly with small perforation) {6}. Ascospores cylindric-suballantoid, non-septate inside living asci, *(9–)13–18(−20) × (3–)3.2–3.8(−4.2) μm {5}, †11–15 × 2.5–3.5 μm, with quite a few very small guttules (LBs) scattered in each half or only towards the ends; overmature 1(−3)-septate, producing one or a few consecutive microconidia at both ends, subglobose or broadly ellipsoid, *2.5–3.3 × 1.9–2.6 μm, with a ± large eccentrical LB. Paraphyses cylindrical or slightly moniliform, smooth, gradually broadening towards the apex, terminal cell *33–60 × 2–5.5 μm, with non- to low-refractive ochraceous to red-brown vacuoles (deep chestnut-brown in dead state).
Habitat: on 3.5–15 mm thick, attached (0.2–1.5 m above ground) or fallen, corticated twigs and branches of Tilia {5}, Salix {1}, Pinus {1}, Ulmus {1}. Phenology: all the year round. Distribution: uncommon in Europe (Spain, Austria, Germany, Denmark, United Kingdom, Sweden, Estonia, Finland) (Dennis 1956; Hansen and Knudsen 2000).
Comments: All parts of the fruitbodies survive complete desiccation, which is unusual in the genus Rutstroemia. The collection on Ulmus sp. resembles Encoelia siparia Baral and Richter (1997), yet deviates from this species by a distinct amyloid ring at the ascal apex that extends to the lower part of the apical thickening. In our multigene (Fig. 1) and the ITS phylogenies (Fig. 2, S4) R. tiliacea was closely related to the type species of the family, R. firma, as well as to R. johnstonii and R. juniperi. ITS data further revealed close affinities of these four species with R. echinophila, R. bolaris, R. sydowiana, R. pseudosydowiana and R. fruticeti. Specimens examined: AUSTRIA, N of Wien, Marfeldkanalweg, 48.30°N 16.35°E, alt 165 m, branch of Ulmus minor, on wood, 17 Nov 2002, W. Jaklitsch (W.J. 2023, H.B. 7279); ESTONIA, Tartumaa, Meeksi, Järvselja Forest Reserve, 58.2833°N 27.32°E, alt. 48 m, on a rotten twig of Tilia, 27 Sep. 2001, K. Pärtel (TAAM 165849, KL211); GERMANY, Sachsen-Anhalt, SW of Freyburg/ Unstrut, SW of Burgheßler, Metzenholz, 51.156°N 11.64°E, alt. 250 m, on bark of a branch of Tilia, 31 May 2009,W. Huth (H.B. 9065); ENE of Freyburg/Unstrut, Alte Göhle, 51.222°N 11.792°E, alt. 195 m, on bark of a branch of Tilia, 21 Jul 2000, M. Huth (H.B. 6734, TAAM 132844, KL160); Baden-Württemberg, NW of Schwäbisch Hall, N of Wackershofen, Am Grundbach, 49.138°N 9.703°E, alt. 330 m, branch of Salix, on bark, 17 Oct 1986, L.G. Krieglsteiner (H.B. 3097); NE of Reichenbach, E of Thomashardt, Lindenallee, 48.75°N 9.505°E, alt. 480 m, branch of Tilia, 1 Jan. 1961, H. Haas (STU H.H. 1030, H.B. 184); Bayern, Oberfranken, WSWof Bayreuth, Wof Oberaufseß, Lindenallee, 49.89°N 11.215°E, alt. 450 m, branch of Tilia, on bark, 11 Jun 1990, H. Engel
(H.E. 13,034, H.B. 4112). SPAIN, Asturias, E of Pola de Somiedo, S of Villarín, 43.097°N 6.199°W, alt. 900 m, on bark of twigs of Pinus sylvestris, 1 Mar 2008, E. Rubio (E.R.D. 4388). SWEDEN, Uppland, Bondkyrka, Gottsunda, substrate unknown, Sep. 1905, K. Starbäck (S-F31483, L. Romell 16533).
Rutstroemia tiliacea. a–c Apothecia (hydrated), c in cross-section (showing pseudosclerotium in wood). d–e Cross-section of apothecium. f-h Ectal excipulum, f cortical hyphae. i Medullary excipulum. j Ascus*.
k–l Ascus apices† in IKI.mCrozier. n–o Asci† in IKI. p Ascospores*, p1 overmature 1-septate, budding conidia, p2 mature, lower left overmature, with 3-septa († in IKI). q Ascus and paraphyses* containing brown vacuoles. Scale bars: a = 5 mm, b–c = 1 mm, d = 100 μm, e = 50 μm, f–j, m–q = 10 μm, k–l = 5 μm. Sources: a, f–h, k, l, m, p1 E.R.D.4388; b, c, j, k, p2, q H.B. 9065; d, e, n TAAM132844; i TAAM165849; o S31483. Photos a, f-h, k, l, m, p1 by E. Rubio Domínguez
Recent Genus
RutstroemiaXeropilidium
Ionomidotis
Recent Species
Encoelia furfuraceaRutstroemia tiliacea
Xeropilidium dennisii